CDX woes

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Back in 2012 on the old workbench forum, I (kind of) got my first CDX working. The unit required the door hinge fix on the eject switch side and I was able to get the CD player working for a short while. Then it started acting up (working intermittently). Resolving that it was an alignment problem with the hinge switches, I put the CDX up and worked on other projects.

Later, I received a second CDX that had good hinges.

I spent the last week trying to get one good functioning CDX out of the two. I actually had the unit playing CDs for one night. The next morning, it wasn't working again.

So far, I have resoldered the griplets on the two main boards of the first CDX. The second CDX looks to be a later version and has nicer looking griplets. For now I haven't touched those.

The problem I am having right now is the CD motor spins all of the time. When the lid is open, I checked all of the switches and they measure as expected. Yet the motor spins. Two days ago the CDX unit started functioning correctly. I could turn power on, open the lid, observe the motor wasn't spinning, insert a CD, hit play and the unit would start right up. It sounded really good when it works. The next morning I turned the unit on, inserted another CD and was surprised the the motor was already spinning the platter. So it broke overnight.

So at various times I have seen both of my CDX main chassis operate correctly while, right now, they both behave the same and will not stop turning.

That makes me suspect the problem is common to both so it would have to be in the common pieces of my latest tests...which are the lid components: eject assembly, lid door motor assembly and control panel assembly. The only thing is - I have seen it work with those same components. Maybe a loose wire somewhere?

As I said earlier, the two switches on the door open motor assembly and the one switch on the door eject assembly appear to be operating correctly. I can measure continuity and open on the switches as the door hinges go through their travel.

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Okay Jacques and Martin....Apparently, the griplet re-soldering fixed the CDX. I did just the servo board first, it didn't fix the problem. Next I did the Decoder board. When I reconnected everything, there it was - the motor powers on stopped. The stopped voltage was less that a volt. I put the cover back on and tried a CD. The CD played.

This is a goofy piece of audio equipment for sure. I wish I had just soldered one griplet then tested before I moved to the next one. It would have been nice to know which part of the circuit was actually causing the problem.

Another strange thing was that I have two CDX units that fail in the same way (motor wouldn't stop spinning), yet the problem must be two separate issues with the main assembly. I thought that was not a likely scenario and the problem must be something common to both. That theory started falling apart when the problem remained regardless of what lid I used.

So I still have the second (CDX 001 in my earlier references) unit that I will put away for now until I get a door motor gear for it. On that unit I had already reworked the griplets but I guess I will have to retry that again. Of course there could be an actual failed component on the unit...but it had worked as recently as last week.

Thanks for the comments Jacques and Søren. One great enjoyment of this forum is with the information members share as projects are worked. I like contributing as I learn about these old audio components. This really is about the only way a vintage audio enthusiast can learn about equipment that is long out of production. I am still very green when it comes to audio repair knowledge but I feel I have learned a lot in the last two or three years. Nothing beats getting hands-on and working with something.

Today I decided to see if I could go ahead and rig this CDX unit to play a CD. I was able to use my fingers to keep the disc secure as it started turning and accelerated to play speed. Sure enough, the laser read the disc and began playing. A very good sign. Here is a picture of the disc playing. One thing to note, when you operate the CDX with everything apart like I have it setup here, you must make sure to raise the main chassis off the surface so the laser mechanism underneath can move. I mention that because it may not be obvious in the picture that the chassis is raised off the table.

I see another thread on the Beoworld Forum that asks about Beoworld losing its mojo. When it comes to the workshop, this is really The Forum to come to. Whatever you call it (mojo, energy, activity), there is a really supportive group here and it is great to have. Maybe other areas of Beoworld feel like they have lost something but for repair questions this is it. As modern electronics gets more and more into micro, surface mounted internals, those pieces may end up too difficult for the "do it yourself" repair guys (like me) to work on. In the meantime, I think there are plenty of vintage repair units out there to keep me busy.

FYI - I don't have anything against modern entertainment systems. I just prefer the older stereo systems for listening to and working on.

Getting back on topic, here is the replacement gear from Jacques (in the bag) and the broken one.

This spare parts CDX unit is now functional again. I say spare parts because I took all of the best looking parts from my two CDX units to make the first, good CDX player I completed earlier in this thread. The remaining parts were all there for a functional second unit except for the broken gear that Jacques sent me.

However, this second unit does have a couple of issues.

Cosmetically, the little holder for the CD is scratched up. Mechanically, the eject side hinge of the CDX is not 100%. It is one that came broken and I had to repair. While the door opens and closes via the door motor okay, the door needs manual help on the eject side to actuate the mechanics that say the door is completely closed. I can press a little on the door (left side) and everything works. When I opened the CDX back up to study the problem, it appears related to the door hinge itself. I think it really needs a new hinge. But...the CDX is usable with this repaired hinge and will work fine in my shop where I intend to use it as a CD source.Another mechanical (electro-mechanical) problem with this CDX is the touch buttons. I originally had problems with this unit. I had to arrange some spacers on the function posts so the touch pads would operate on some of the functions. That takes repeated opening and closing back up of the CDX in order to get everything adjusted. Right now, all of the control buttons work except the Display selection and the Reverse (<<) button. I tried getting that adjusted but haven't had success yet. I'm not going to spend anymore time right now to get those two things working as I have to move on to my next projects and this CDX is already playable in my shop.

Here is an old picture of the adjustment for the CDX touch buttons. I'm going to go listen to some CDs now.